Growth Hormones

Front 1

What are the stimuli that enhance prolactin secretion?

Back 1

1) TRH
2) nursing
3) sleep
4) opiods
5) serotonin
6) estrogen
7) stress
8) pregnancy

Front 2

What is the synthesis pathway of growth hormone look like?

Back 2

1) somatotrophs of anterior pituitary synthesize the preprohormone
2) hormone is released in pulsatile manner

Front 3

What is the physiologic action of growth hormone (5)?

Back 3

1) promote growth/body mass
2) increases nutrient synthesis in tissues
3) increases fat utilization
4) decreases carb utilization
5) stimulates IGF-1 release

Front 4

What is the function of IGF-1?

Back 4

1)stimulates cartilage growth

Front 5

What decreases IGF-1 production?

Back 5

↓ insulin
↓ calories

This would make sense because you dont want to grow when you are starved

Front 6

What causes the release of GH? (10)

Back 6

1) slow wave sleep
2) stress
3) exercise
4) arginine infusion
5) hypoglycemia
6) high serum AA
7) cortisol and thyroid hormones
8) NTs
9) ghrelin
10) GHRH

Front 7

Is GH secretion more in men or women?

Back 7

women because of estrogen

Front 8

What are things that cause an inhibition of growth hormone? (6)

Back 8

1) hyperglycemia
2) ↑ FFA
3) cortisol
4) obesity
5) somatostatin
6) obesity

Front 9

When do you secrete the most GH?

Back 9

-during puberty
-at night

Front 10

What two hormones regulate the release of growth hormone?

Back 10

-GHRH
-somatostatin

Front 11

How does IGF-1 also regulate growth hormone secretion?

Back 11

indirectly - stimulates secretion of somatostatin
directly - acts on anterior pituitary to inhibit GH

Front 12

What are the secondary messengers of GH?

Back 12

1) GH binds receptor
2) secondary messengers Janus Kinase is activated
3) Janus Kinase activates PLC, STATs, GRB2 and IRS
4) IRS: ↑PI-3 kinase
GRB2: ↑ gene expression
STATs: ↑ gene expression
PLC: ↑ Ca

Front 13

What happens in growth hormone XS?

Back 13

1) gigantism
2) acromegaly
3) diabetogenic

Front 14

What is the difference between acromegaly and GH?

Back 14

gigantism - childhood XS GH
acromegaly - adult XS GH

Front 15

How is GH involved in Kwashiorkor?

Back 15

starvation causes hi GH levels

Front 16

What causes GH deficiency?

Back 16

1) adults: hypoglycemia
2) children: dwarfism

Front 17

What causes Laron dwarfism?

Back 17

↓ GH receptors
↓ IGF-1 receptors

Front 18

What are the sources of somatostatin?

Back 18

1) hypothalamus
2) D cells of pancreatic islets of L
3) GI tract

Front 19

What is the physiological action of somatostatin?

Back 19

1) inhibits release of lots of things
2) decreases GI blood flow and mobility
3) increases GI water/electrolyte resoprtion

Front 20

What are the things that somatostatin inhibits the release of?

Back 20

1) GH
2) prolactin
3) TSH
4) insulin
5) glucagon
6) GI hormones

Front 21

What is the mechanism of action of somatostatin?

Back 21

1) binds PM receptor
2) ↓ cAMP
3) ↓ Ca levels
4) ↓ cAMP
5) block K channel
6) ↓ exocytosis

Front 22

What is octreotide and what is it used for?

Back 22

-Octreotide is an analog of somatostatin
-it is used for treating acromegaly, insulinoma, TSH and VIPoma

Front 23

What is a hormone with the suffix -oma at the end mean?

Back 23

there is a tumor secreting that hormone

Front 24

Explain the synthesis of prolactin?

Back 24

mammotrophs in anterior pituitary synthesize it as a pre-pro-hormone

Front 25

What are the two physiological actions of prolactin?

Back 25

1) initiates and maintains milk production
2) intiates and maintains development of breast tissue
3) influences immune response and reproductive function

Front 26

Are levels of prolactin higher in men or women?

Back 26

higher in women because of estrogen

Front 27

What are stimuli that inhibit prolactin release?

Back 27

1) bromocriptine mesylate
2) dopamine
3) somatostatin

Front 28

What is bromocriptin mesylate? What is it used for?

Back 28

dopamine analog that is used to treat prolactinoma

Front 29

What is the regulation of prolactin?

Back 29

1) tonic inhibition: supress synthesis and release of prolactin
2) TRH promotes PRL release

Front 30

What is the mechanism of prolactin action?

Back 30

1)binds to PM receptors
2)activates Janus Kinase
3) phosphorylate STAT proteins
4) expression of genes

Front 31

What happens in prolactin deficiency?

Back 31

decreased milk production

Front 32

What happens with excess prolactin in males?

Back 32

impotency bc
↑ prolactin
↓ testosterone
↓ sperm production

Front 33

What happens with excess prolactin secretion in females?

Back 33

↓ GnRH
↓ LH
↓ FSH